Speed responsive apparatus



June 1, 1937. .1. w. LIVINGSTON SPEED RESPONSIVE APPARATUS Filed July11, 1956 5 Sheets-Sheet l QDQ amQ Q N E SQQ NN Q 3 nnentor $5012 John(Z). Lil/i His (Ittorneg June 1, 1937. J w UWNGSTON 2,082,166

SPEED RESPONS I VE APPARATUS John (0. mgszon.

BY n I i 7 H15 ATTORNEY June 1, 1937. w: LMNGSTON 2,082,166

SPEED RESPONSIVE APPARATUS Filed Julylll, 1936 5 Sheets-Sheet 4 INVENTORHA5 ATTORNEY June I,' 1937- J. w. LIVINGSTON SPEED RESPONSIVE APPARATUS5 Sheets-Sheet 5' Filed July ll, 1936 |NV EN TOR John (1/. uzyszozz.

HIS ATTORN EY Patented June 1 1 937 UNITED STATES PATENT OFFI SPEEDRESPONSIVE APPARATUS Application July 11, 1936, Serial No. 90,161

30 Claims.

. sponsive apparatus.

I will describe two forms of apparatus embodying my invention, and. willthen point out the novel features thereof in claims.

In the accompanying drawings, Fig. 1 is a view partly in elevation,partly in section, and partly diagrammatic, showing one form of speedresponsive apparatus embodying my invention. Fig. 2 is a sectional viewof the apparatus shown in Fig. 1 taken on the line II-1I of Fig. 1. Fig.3 is a detail view of the driving plate I8 forming part of the apparatusshown in Fig. 2. Fig. 4 is a detail sectional view taken on the lineIV-IV of Fig. 2. Fig. 5 is a diagram showing graphically the operatingcharacteristics of a portion of the apparatus illustrated in Fig. 1.Fig. 6 is a vertical sectional view showing another form of speedresponsive apparatus embodying my invention. Figs. '7 and 8 aresectional views taken on the lines VII-VII and VIII-VIII, respectively,of Fig. 1.

Similar reference characters refer to similar parts in-each of theseveral views.

Referring first to Figs. 1 and 2, the reference character I designates acasing which is adapted to be secured, in any suitable manner, to arailway car or locomotive adjacent one end of one of the axles 2 of thecar or locomotive, and which is closed at its outer end by a removablecover 3. Disposed within the casing l is a frame A, one end of which ispinned to a shaft 5 that is journaled in the casing I at the bottom ofthe casing. The end of the frame l opposite to the shaft 5 is providedwith a recess 6 which slidably receives a block or roller I mounted onan eccentric pin 8 formed on one end of a shaft 9. The shaft 9 isjournaled in a suitable bearing Ill provided in the side of the casingl, and secured to this shaft on the outside of the casing is a handle Hby means of which the shaft may be rotated through an angle ofsubstantially 180 from the position shown in Fig. l. The parts are soproportioned that when the shaft 9 is rotated to the position shown, theblock 1 will cooperate with the cam recess 6 to rotate the frame 4 andshaft 5 in a. clockwise direction as viewed in Fig. 2 to what I shallterm a normal extreme position, but that, when the shaft 9 is rotatedthrough an angle of 180 from the position shown, the block I will thencooperate with the cam recess 6 to rotate the frame 4 and shaft 5 in acounter-clockwise direction to another extreme position.

A ring member I2 is pinned to a shaft 13 which is mounted to oscillatein the sides of the frame 4, and pivotally attached to this ring memberby means of diametrically opposite pivot pins l4 spaced 90 from theshaft I2 is a driving member I5 comprising two outwardly curved arms l5and l5 secured at one end to a circular web 15. The edge of the web I5is rounded, and the parts are so proportioned that, when the frame 4occupies its normal position in which it is shown in the drawings, theweb l5 will enter a circular hole I! provided in a driving plate l8secured to the end of the axle 2, but that, when the frame 4 is rotatedto its other extreme position, the web l5 will then be withdrawn fromthe hole ll. The outer face of the driving plate l8 adjacent the hole I!is countersunk so that, when the frame 4 is moved to its normal positionfrom its other position, the Web l5 will readily enter the hole 11. Asshown in Fig. 3, the hole, I! is eccentric with respect to the axle 2,and the fit between the rounded edge of the web 15 and the hole I! issuch that when the axle 2 is rotated, the Web will be free to rotatewithin the hole I1, and also to rock about the axis of the shaft 13. Itwill be seen, therefore, that rotation of the axle 2 will impart anoscillatory movement to the ring member 12 and shaft l3, and that thefrequency of oscillation of the ring member and shaft will increase ordecrease according as the speed of the axle 2 increases or decreases. Itfollows, therefore, that the frequency of oscillation of the shaft l3will increase or decrease as the linear speed of the car or locomotiveof which the axle 2 forms a part increases or decreases.

Mounted to oscillate on the shaft I3 within thering member I2 is aninertia member 28 which, as here shown, is in the form of a hollowsphere, although this particular form is not essential to my invention.A rocker 2| is pinned to the shaft l3 within the inertia member 20, andsecured to, but insulated from, the opposite sides of the rocker 2| aretwo resilient contact fingers 22 and 23. These contact fingers areprovided at their free ends with low resistance contact members 22 and23 which contact members cooperate respectively with two similar contactmembers 24 and 25 mounted on a rigid U-shaped conducting bracket 26which is secured to, but insulated from, the inertia member at one side"of the inertia member. The parts are so proportioned that when the axle2 is at rest, so that the inertia member is stationary, the contactmember 22* will engage the contact member 24 to close a contact 22 -24and the contact member 23 will engage the contact member 25* to closeacontact 23 -25 and that, under these conditions, the fingers 22 and 23will each be flexed a certain amount, Associated with each contactfinger is a fixed stop 21 which limits the position to which theassociated finger can move due to its inherent bias when the contactcontrolled by the finger is opened. r

The lower-end of the rocker 21 is provided with an extension 2 l theopposite sides of which cooperate with shoulders 20 and 20 formed on therocker to limit to an amount which will prevent damage to the parts, themotion of the inertia member relative to the rocker in the event ofabnormal operation of the governor due, for example, to breakage of acontact finger. This extension, however, "does not engage the shouldersduring normal operation of the governor.

External electrical connections to the contact fingers 22 and 23 aremade-by means'of two conductors 29 and 33 which extend into the inertiamember 29 through a hole I 3 drilled in the shaft l3,'and are connected"at their inner ends to'the contact fingers. The outer ends of theseconductors are con'nected'to arcuate con tact segments 31 and 32 moldedin'an insulating member 33 which is secured to the'outer end of theshaft l3 to oscillate therewith. The member 33 is sealed in an auxiliarycasing 34 which is H fastened to one side of the frame 4, wherebyforeign matter is prevented from entering the inertia member. Mounted intheauxiliary casing 34 in any suitable manner not shown are two brushes35 and 36 which are biasedinto engagement with the contact segments3land'32, respectively, and which are connected to conductors 3! and38,and 38 are carried through ahole 40 drilled in the frame 4, and througha hole 4| drilled in the shaft 5, and are connected at their with twocontact fingers 42 and 43forming part of a cut-out switch- 8. Thefingers 42 and 43 of the cut-out switch S are fastened to an insulatingblock 44 which, in turn, is fastened-t the shaft 5, and these fingerscooperate at their free ends with fixed contact members 45 and 46,respectively. The cut-out switch S is disposed in a second auxiliarycasing 41.which is cast integrally with the main casing.-The parts areso proportioned that when the frame 4 occupies its normal position, thefingers42 and 43-will engage the contact members 45 and 46, respec-'tively, to close contacts 42-45 and 43-46, but that, when the frame 4 isrotated to its other extreme position, the resultant rotation of theshaft will rotate the fingers-to positions in which the contacts 42-45and 43-46 are open.

The apparatusalso includes a'reactance X and an electroresponsiveindicating device here shown as a relay R. The'reactance X and relay R.are

respectively. The conductors 31- free ends connected in series in acircuit which passes from terminal B through a wire 48, contact 42-45,wire 31, brush 35, contact segment 3|, wire 29, contact finger 22,contact 22 -24 bracket 26, contact 23 -25 contact finger 23, wire 30,contact segment 32, brush 36, wire 38, contact 43-46, wire 49, reactanceX, wire 50, the winding of relay R, and wire 5| to terminal 0. Connectedin multiple with reactance X and relay R in the circuit just traced isan asymmetric unit A which is so disposed that it will offer itshighestresistance to current which tends to flow through the branch pathincluding this unit from terminal B to terminal 0. Relay R is preferablymade slow acting for reasons which will appear hereinafter.

The operation as a whole, of the portion of the apparatus thus fardescribed is as follows: As was previously pointed out, when the axle 2is rotated, the shaft 53 is oscillated at a frequency which increases asthe speed of rotation of the axle Zincreases and since the rocker 2| issecured to the shaft l3, it will be obvious that any oscillation of thisshaft will cause corresponding oscillation of the rocker. Anyoscillation of the rocker, in turn,'will cause an accelerating force tobe exert-ed on the inertia member 28, first in one direction and then inthe other during each cycle, through the medium of the contact fingers22 and 23, so that the inertia member will also be made to oscillate.The magnitude of the force required to accelerate the inertia memberwill, of course, increase with increases in the frequency of oscillationof the rocker according to the square of the frequency, and it will beseen, therefore, that as long as the frequency of oscillation of therocker remains below some frequency which I shall term the criticalfrequency, and which depends upon the stiffness of the contact fingers22 and 23, and the inertia of the inertia member, the contact fingerswill transmit to the inertia member sufhcient accelerating force tocause the inertia member to oscillate cyclically through its maximumamplitude without deflecting either finger a sufficient amount to openthe associated contact 22 -24 or 235 -255 during any part of a cycle. Assoon, however, as the frequency of oscillation of the rocker exceeds thecritical frequency, the contact fingers 22 and 23 will no longer be ableto transmit to the inertia member sufficient accelerating force to causethe inertia member to oscillate cyclically through its maximumamplitude, and under these conditions, the oscillations of the inertiamember will decrease in amplitude until the maximum inertia force isjust equal to the maximum force exerted by the contact fingers 22 and23. The inertia member Zfl-Wlll then lag in phase with respect to therocker 2i, and since the amplitude of oscillations of the rocker remainssubstantially constant, it will be apparent that during the greater partof one-half of each cycle the contact finger 22 will be deflected beyondits normal amount and the contact Eli will be open, whereas during thegreater part of the other half of each cycle the contact finger 23 willbe de flected beyond its normal deflection, and the contact 2-2= 2 iwill be open. It will also be apparent that since the rocker and theinertia member are out of step for all frequencies of the rocker abovethe critical frequency they will be moving at different speeds whentheir relative positions are such that the contacts H -25 and 22 -24areclosed, and it follows that the circuit through these contacts willbe closed only a small portion of each half cycle under theseConditions. It should be pointed out that at very high frequencies ofoscillation of the rocker the inertia member will remain substantiallystationary, and the oscillations of the rocker will be absorbed almostwholly by the contact fingers.

As was previously pointed out, the contacts ZZ -Zd and Zi -45 areconnected in series in the circuit for reactance X and relay R, and itfollows that when these contacts are both closed, this circuit will beclosed and current will then be supplied to relay R. It will be readilyunderstood, however, that due to the inductance of this circuit, thecurrent in the winding of relay R will not build up to its Ohms lawvalue immediately upon the closing of the circuit for the relay, butwill build up according to the time constant curve of the circuit.Likewise, when either contact is opened, the circuit for reactance X andrelay R will become interrupted, and the supply of current to the relaywill therefore be out off. At the instant the supply of current to therelay is cut off, the current in the winding of the relay will start todecrease, but due to the energy stored in this winding and in thewinding of reactance X, a circulating current will be set up in theclosed circuit including the winding of the relay, reactance X, andasymmetric unit A, and this circulating current will delay the decay ofcurrent in the winding of the relay in a manner which depends upon thetime constant of the closed circuit formed by the relay, the reactanceand the asymmetric unit. It will be readily understood, therefore, thatwhen the circuit through the relay is continuously closed, the currentinthe relay will build up to its Ohmslaw value, but that, when the circuitis periodically interrupted, the current will not have an opportunity tobuild up to its Ohms law value, and, under these conditions, the relaywill be supplied with current the average value of which will dependupon the ratio of the open circuit time of the circuit to the closedcircuit time, and upon the frequency of interruption of the circuit. Itwill also be readily understood that as the frequency of oscillation oftherocker increases beyond the critical frequency, the ratio of the opencircuit time to the closed circuit time will increase rapidly, and thatthe frequency of interruption of the circuit will also increase, so thatthe average value of the current in the relay winding will decreaserapidly. A typical curve 59 indicating the manner in which the averagevalue of the current which is supplied to the relay winding varies withvariation in the frequency of oscillation of the rocker is shown in Fig.5. From an inspection of this curve it will be seen that at allfrequencies of oscillation of the rocker below the critical frequency,the average value of the current in the relay winding is constant. Thereason for this is that, as was previously pointed out, at allfrequencies below the critical frequency, both contacts EF -25 and 23-45 remain continuously closed, and the current in the winding of therelay builds up to, and remains at, its Ohms law value. As soon as thefrequency of oscillation of the rocker exceeds the critical frequency,however, so that the contacts M' -24 and 23 -'25 start to alternatelyopen, the average value of the current in the relay winding starts todecrease, and as the frequency of the oscillation of the rockercontinues to increase, the current decreases more and more rapidlyuntil, at a narrow band of frequencies just a little above the criticalfrequency,

the decrease is very rapid. As the frequency of oscillation of therocker further increases beyond this narrow band of frequencies, thedecrease in current becomes less marked until at very high frequenciessubstantially no further decrease in current takes place.

As was also pointed out hereinbefore, relay R is preferably aslow-acting relay, and it will be readily understood, therefore, that byproperly designing this relay, this relay ,may be made to respond to theaverage value of the current supplied to its winding and not to theinstantaneous value. It will be seen, therefore, that by designing thisrelay in such manner that its pick-up and release values fall on someportion of the curve 59, the relay will pick up at all frequencies ofoscillation of the rocker below the frequency corresponding to thepick-up value, and will be released at all frequencies of oscillation ofthe rocker above the frequency corresponding to the release value. Forexample, if the relay is provided with a pick-up value indicated by theline fill in Fig. 5, and with the release value indicated by the line Siin Fig. 5, the relay will be picked up at all frequencies of oscillationof the rocker below that indicated by the vertical line 62, and will bereleased at all frequencies of oscillation of the rocker above thatindicated by the vertical line 83. It will be readily understood, ofcourse, that as the frequency of oscillation of the rocker is increasedfrom some value below the critical frequency to some value beyond thefrequency at which the relay releases the relay will remain picked upuntil the frequency at which the relay releases is reached, and that asthe frequency of oscillation of the rocker is decreased from some valuewhich is higher than the frequency at which the relay releases to somefrequency which is below the frequency at which the relay picks up,relay will remain released until the frequency at which the relay picksup is passed. It will be remembered that the critical frequency of therocker 2! depends upon the proportioning of the parts, and it followsthat by properly selecting the electrical and mechanical elements of theapparatus, relay B may be made to pick up and release its armature atany desired frequency of oscillation of the rocker, and hence at anydesired linear speed of the car or locomotive with which the rocker isoperatively connected. It will also be seen that by adjusting thepick-up and release values of relay R to such values that they fall onthe steep portion of the curve 59 as indicated by the lines 5E! and iii,the relay may be made to pick up and release its armature at frequencieswhich differ in magnitude by only a small amount. This is particularlydesirable when the relay is to be utilized for controlling circuits inconnection with speed control systems for railroads.

When relay R is picked up, its front contact 56--58 is, of course,closed, and when this relay is released, its back contact 5858 isclosed. The contacts of this relay may be utilized to control thecircuits for any suitable electroresponsive device or devices in suchmanner that the device or devices will occupy one position when therelay is energized and another position when the relay is deenergized.For example, when the apparatus is operatively connected with some partof the running gear of a car or locomotive, as is the case in theembodiment illustrated, so that the frequency of oscillation of therocker ill varies with the linear speed of the car or locomotive, relayR may be utilized to control a speed governing device for the car orlocomotive. As here shown, relay R controls a brake controlling magnetE'which applies the brakes on the car or locomotive when this magnet.becomes deenergized.

The circuit forv magnet E is; carried. over; front:

contact 58-458 of relay R. It will be apparent, therefore, from theforegoing, that as long as the speed of the car or locomotive is belowsome predetermined speed, magnet E will be energized, but that, if thespeed of the car or locomotive increases beyond this speed, magnet Ewill become deenergized, thus enforcing a low speed limit on the car orlocomotive. It should be definitely understood, however, that apparatusembodying my invention is in no way limited to this particular-use.

It should be particularly pointed out that with the apparatusconstructed in the manner described" the speed responsive apparatus maybe rendered inactive by rotating the lever H from the position shown toits opposite extreme position'. This rotation of the lever disengagesthe web l5 of'the driving member l5 from the hole I! in the drivingplate l8, and also rotates the contact fingers 42' and 43 of the switchS to positions in which the contacts 42-45 and 43-- l$ are open, thusinterrupting the circuit for relay R, and hence deenergizing this relay.When relay R is deenergized in this manner, the brake magnet will berendered ineffective to apply the brakes bymeans which forms no part ofmy pres ent' invention, and which is therefore not shown in thedrawings.

One advantage of the apparatus shown in Figs. 1 and 2 is that itprovides a convenient means for operatively connecting the apparatuswith a car or locomotive.

Another advantage of the apparatus shown in Figs. 1 and 2 is that sincethe driving forces are all transmitted from the rocker to the inertiamember through the medium of the resilient contact fingers, these forcesare limited to relatively small values, thus permitting the structuralstrength requirements of the'parts to be reduced to a minimum.Furthermore, there is no shock to the parts which would cause damage anddecrease the life of the apparatus.

Referring now to Figs. 6, 7, and 8, the modified form of apparatus hereillustrated comprises a driving member in the form of a crank having a.

hollow crankshaft 65 The crankshaft 65 is journaled in a bushed bearing66 formed in a suitable casing 61, and has attached thereto on theoutside of the casing a driving member 68 which is adapted to beconnected with some reciprocating part of a car or locomotive in suchmanner-that when the car or locomotive is in motion, the crank will beoscillated at a frequency.

which is proportional to the speed of the car or locomotive. The crankarm 65 of the crank 65 extends upwardly from the crankshaft and carriesa crank pin 65? which pivotally supports a floating rocker lever 69. Therocker lever 69 is slotted at its .lower end, and cooperates with asliding block 10 pivoted on a pin H secured to a disc-shaped inertiamember 12. The inertia member 12 is mounted to oscillate on.a headedmandrel 13 which extends into one end of the crankshaft and is securedthereto by means of a headed nut 14. The mandrel i3 is provided with atapered shank portion [3 which cooperates with a correspondingly taperedopening in the endof the crankshaft, and with a screwthreaded inner endl3 which is screwed into a tapped hole formed in the inner end of thenut 14, whereby the mandrel isheld in a fixed longitudinal position withrespect to the hollow crankshaft A laterally projecting pin is securedto the rocker lever 69 intermediate its ends, and pivotally mounted onthis pin is a contact operating bar 76. This bar is provided at itsopposite ends with two insulating members 11 and 78 which cooperaterespectively with two contact fingers 19 and 80. The contact fingers 18and 19 are'secured at their lower ends, as by riveting, to resilientstrips 8| and 82, respectively, of suitable material, such as phosphorbronze, and the lower ends of the strips 8| and 82, in turn, are securedto ears 83 and 84 formed on the ends of an angle bracket 85. When theapparatus is in operation, the fingers 19 and 80 are at times oscillatedat a rapid rate in a manner which will appear presently, and to preventbreakage of the resilient strips BI and 82 due to the resultant flexingof the strips, the ears 83 and 84 are bent outwardly, as shown in Fig.7, in such manner that any flexing of these strips which occurs will bein the form of a gradual curve. The angle bracket 85 is secured to aninsulating terminal'board 86 which is clamped between the casing er anda cover 87 which closes the adjacent end of the casing, whereby thefingers 19 and 8!] are electrically connected together by means of thebracket 85, but are insulated from the casing. The contact fingers l9and 80 are provided at their upper ends with low resistance contactmembers 19 and 88 which contact members cooperate, respectively, withtwo similar fixed contact members 88 and 89 provided on contact screws88 and 89, to form contacts NF -88 and 80 -89 The contact screws 88 and89 are adjustably mounted in laterally projecting lugs 96 and 9H formedon contact brackets 90 and 9| of suitable with the contact brackets 90and 91 are terminal pcstsizsfir' an'd 93 which facilitate makingexternal connections with the fixed contact members.

The contact fingers are biased toward each other,

insulating members 1'! and 78 are guided during movement of the fingersl9 and 89 by means of guides 91 and 98 which are riveted to the fingers,and which have rounded portions 9! and 98 for the reception of theinsulating members. The parts are so proportioned that the axis of thepin 75 will align with the axis of the mandrel 13 when the rocker 69occupies certain positions, and the contacts are so adjusted that whenthe rocker occupies any position in which the axis of the pin 15 alignswith the axis of the mandrel '13, both contacts will be closed and therewill be practically no clearance between the insulating pieces 11 and I8and the associated guides 97 and 98.

The terminal board 86 is provided near its center 7,

with a slot 86 which receives the pin 15 and boss of the arm 69 in whichthis pin is mounted with suificient clearance to permit free movement ofthe rocker in response to movement of the crank 65. The contacts of theapparatus are adapted to be included in a control circuit for relay Rsimilar to that shown in Fig. 1, and I have accordingly shown the wires48 and 45) connected with the terminal posts 92 and 93. It will be seen,therefore, that the circuit for relay B when the apparatus isconstructed in the manner shown in Fig. 2 will pass from terminal Bthrough wire 48, terminal post 92, contact bracket 90, contact le 68contact finger l9, strip- 8|, 5 bracket 85, strip 82, contact finger 80,contact St -89 bracket ti, wire 49, reactance X, wire 5%, the winding ofrelay R,,and wire 5| to terminal 0, the asymmetric unit A beingconnected in multiple with the reactance X and the winding of relay R inseries.

The operation of the apparatus shown in Figs. 6, '7, and 8 is asfollows: When the crank 65 is oscillated, the upper end of the rocker t9will be constrained to move with the crank pin 55, and it will beapparent that when the upper end of the rocker 69 is being moved towardthe right, as viewed in Fig. '7, a force will be exerted on the contactfinger 89 through the medium of the pin 15, operating member 75, andinsulating piece 18 which force will tend to move the finger 80, inopposition to the bias oi the spring 94, to a position in which thecontact Bil -Alfi is open, and an opposite force will be exerted on theinertia member 12 through themedium of the pin H and sliding blocklii,-which latter force will tend to rotate the inertia member in aclockwise direction, whereas, when the upper end of the arm 69 is beingmoved toward the left, as viewed in Fig. '7, a force will then beexerted on the contact finger 79 through the medium of the pin 75,operating member 75, and insulating piece 11, which force will tend tomove this finger in opposition to the bias of the spring 9% to aposition in which the contact l9 li9 is open, and an opposite force willbe exerted on the inertia member 72 through the medium of the pin ii andsliding block 70, which latter force will tend to rotate the inertiamember in a counter-clockwise direction. It follows, therefore, thatwhen the crank 65 is being oscillated, an accelerating force will beexerted on the inertia member first in one direction through the mediumof the one contact finger, and then in the other direction through themedium of the other contact finger, so that the inertia member will tendto oscillate in response to the oscillation of the crank 65. Themagnitude of the force required to accelerate the inertia member will,of course, increase with increases in'the frequency of oscillation ofthe crank 65 according to the square of the frequency, while the forcewhich is exerted on the inertia member tending to accelerate it willdepend upon the stiffness and initial tension of the spring 94. Thestiffness and initial tension of the spring 94 are so chosen that aslong as the frequency of oscillation of the crank 65 remains below somefrequency which I shall term the critical frequency, the acceleratingforce required to accelerate the inertia member will not be sufiicientto overcome the tension of the spring 94 and cause the contact fingersto move, and it will be seen, therefore, that as long as the frequencyof oscillation of the crank remains below the critical frequency, thepivot pin 75 will remain stationary, and the inertia member will operatecyclically through its maximum amplitude without causing either of thecontacts IS -88 or St -433 to become opened. As soon, however, as thefrequency of oscillation of the crank exceeds the critical frequency,the accelerating force required to accelerate the inertia member will begreater than the force exerted on the contact fingers by the spring EM,and under these conditions, the 75 spring 84 will stretch duringalternate half cycles during alternate half cycles will continue to in-.

crease, thus causing the amplitude of oscillation of the inertia memberto further decrease until at very high frequencies of oscillation of thecrank, the pin 7! will become practically stationary, and the fingers l9and 88 will be moved through a relatively large angle during alternatehalf cycles. It will be seen, therefore, that with the apparatusconstructed in the manner shown in Figs. 6, '7, and 8, the contacts iil88 and SO -89 will operate to interrupt any circuit in which thesecontacts are included in substantially the same manner that the contacts23*---25= and Ev -24 of the apparatus shown in the preceding viewsoperate to interrupt any circuit in which the contacts H -i i and Zi -45are included and that, as a result, relay R, when controlled by theapparatus shown in Figs. 6, '7, and 8 will function in substantially thesame manner that it functions when controlled by the apparatus shown inFigs. 1 and 2.

One advantage of the apparatus shown in Figs. 6, '7, and 8 is that thereare no moving electrical connections.

One advantage of either form of apparatus embodying my invention is thatit is compact and has relatively few moving parts.

Another advantage of either form of apparatus embodying my invention isthat the'ratio of the open circuit time to the closed circuit time ofthe circuit for relay R increases very rapidly as soon as the criticalspeed is passed, thus making it possible to use a standard relay inconnection with the apparatus.

It should be particularly pointed out that while in describing myinvention I have shown an inductance connected in series with relay R inthe control circuit for this relay, and have also'shown an asymmetricunit connected in multiple with the reactance and relay in the circuitfor the relay, due to the high ratio of open circuit time to the closedcircuit time which is provided by the contact arrangement for all speedsof the rocker beyond the critical speeds, the apparatus may besatisfactorily operated without the use of the reactance and rectifierin connection with the relay.

Although I have herein shown and described only two forms of speedresponsive apparatus embodying my invention, it is understood thatvarious changes and modifications may be made therein within the scopeof the appended claims without departing from the spirit and scope of myinvention.

Having thus described my invention, what I claim is:

1. Apparatus responsive to the speed of a movable body comprising apivoted inertia member, a conducting bracket secured to said inertiamember, two contact members secured to said conducting member, a rockeradapted to be oscillated at a frequency which varies with the speed ofthe body, two resilient contact fingers secured to said rocker, twoconducting members secured to said two contact fingers respectively andeach cooperating with a different one of said the amplitude of osfirstmentioned contact members to form a contact, said contact fingers beingso arranged and the parts being so proportioned that both contacts arebiased to closed positions and that when said rocker is oscillated anaccelerating force will be imparted to said inertia member first in onedirection and then in the other direction during each cycle through themedium of said contact fingers, and an electroresponsive indicatingdevice controlled by said two contacts connected in series.

2. Apparatus responsive to the speed of a movable body comprising ashaft which is-oscillated at a frequency which varies with the speed ofthe body, an inertia member-pivotally mounted on said shaft, aconducting bracket secured to said inertia member and provided with twocontact members, a rocker secured to said shaft, two

resilient contact fingers secured to said rocker and each provided witha contact member which cooperates with a different one of said firstmentioned contact members to form a contact, each said finger beingflexed in a manner which biases the associated contact to its closedposition, and an electroresponsive indicating device controlled by saidcontacts.

3. Apparatusresponsive to the speed of a movable body comprising a shaftadapted to be oscillated at a frequency which varies with the speed ofthe body, a first member secured to said shaft=to oscillatetherewith,.an inertia memberpivotally mounted on said shaft, -meansincluding a first resilient contact finger and. a first contactcontrolled by said first finger for imparting an accelerating force tosaid inertia member in one direction during one portion of eachoscillation of saidinertia member, means including a second resilientcontact finger and a second contact controlled by said second finger forimparting an accelerating .force 'to said inertia member in a directionopposite to thatrimparted to said member by said first finger duringanother portion of each'oscillationof saidinertia member,'both saidcontactsbeingbiased'to closed positions, and anelectroresponsivetindicating device controlled by said two contactsconnected in series.

4. Apparatus responsive to the speed of a movablebody comprising ashaftadaptedtozbe oscillated at a frequency which 'varies with the speed ofthe body, a hollow inertia member mounted to oscillate -on said shaft,'a rocker pinned to said shaft withinsaid inertia member, meansincluding two contact fingers and a contact controlled by each fingerfor imparting to said inertia member in response to oscillation of saidrocker an accelerating force which-periodically changes its directionand. an electroresponsive indicating device controlled bysaidtwocontacts.

5. Apparatus responsive to thespeed of a movablewbody comprising-zashaft adapted to be oscillated at a frequency which varies with thespeed of the body, a hollow inertia member mounted to oscillate on saidshaft, a rockerpinned to said shaft within said inertia :member, twocontact members secured to said inertia member, two resilient contactfingers secured to said rocker and each provided with a contact memberwhich cooperates-with a different one of said first mentioned contactmembers to form a contact, each said contact being biased 'to a closedposi-- tion by the associated contact finger, and an electroresponsiveindicating device controlled by said two contacts connected in series.

6'. In combination with a car axle, a 'plate secured to said axle andprovided with a circular plate, a shaft journaled in said frame, a ringmember pinned to said shaft, a driving member provided with two curvedarms which are pivotally connected to said frame at points spaced fromsaid shaft, said driving member also being provided with a web whichenters the hole in said plate, whereby rotation of said axle will causeoscillation of said shaft, an inertia member pivotally mounted on saidshaft, a rocker pinned to said shaft, means including two contactfingers and a contact controlled by each finger for imparting to saidinertia member in response to oscillation of said rocker an acceleratingforce periodically changing in direction, and an electroresponsiveindicating device controlled by said contacts.

'7. In combination with a car axle, a plate secured to said axle andprovided with a circular hole which is eccentric with respect to theaxis of said axle, a frame mounted adjacent said plate, a shaftjournaled in said frame, a ring member pinned to said shaft, a drivingmember provided with two curved arms which are pivctally connected tosaid frame at points spaced 90 from said shaft, said driving member alsobeing provided with a web which enters the hole in said plate, wherebyrotation of said axle will cause oscillation of said shaft, an inertiamember in the form of a hollow spheremounted to oscillate on said shaftwithin said ring member, a rocker pinned to said shaft within saidinertia member,- means including two contact fingers and a contactcontrolled by each finger for imparting to said inertia member inresponse to oscillation of said rocker an accelerating force whichperiodically changes in direction, and an electroresponsive indicatingdevice controlled by said contacts.

8. In combination with a car axle,-a plate secured to said axle andprovided witha circular hole which is eccentric with respect to the axisof said axle, a frame mounted adjacent said plate, a shaft journaled insaid frame, aring member pinned to said shaft,a driving member providedwith two curved arms which are pivotally connected to said frame atpoints spaced 90 from said shaft, said driving member also beingprovided with a web which enters the hole in said plate, wherebyrotation of said axle will cause oscillation of said shaft, an inertiamember'in the form of a hollow sphere mounted to oscillate on said shaftwithin said ring member, a rocker pinned to said shaft within saidinertia member, two fixed contact members secured to said inertia memberwithin said inertia member, two resilient contact fingers secured tosaid rocker and each provided with a contact member which cooperateswith a, different one of said fixed contact members to form a contact,said contact fingers being flexed in a manner to bias both said contactsto their closed positions, and an electroresponsive indieating devicecontrolled by said two contacts connected in series.

9. In combination with a car axle, a plate secured to one end of saidaxle and provided with a circular hole which is eccentric with respectto the axis of said axle, a fixed housing enclosing said plate, a firstshaft journaled in said housing, a frame pinned to said shaft in suchmanner that said frame is movable toward and away from the axle betweena normal extreme position and-.

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another exftreme position, means cooperating with the free end of saidframe for moving said frame between its two extreme positions, a secondshaft journaled in said frame, a ring member pinned t said second shaft,a driving member provided with two curved arms which are pivotallyattached to said ring member at diametrically opposite points spacedfrom said second shaft, said driving member also being provided with acircular web which is adapted to enter or be withdrawn from the hole insaid plate according as said frame occupies its normal extreme positionor its other extreme position, the parts being so proportioned that whensaid web is within the hole in said plate and said. axle is rotated saiddriving member and said shaft will be oscillated, an inertia memberpivotally mounted on said shaft, means including two contact fingers anda contact controlled by each finger for imparting to said inertia memberin response to oscillation of said rocker an accelerating force whichperiodically changes in direction, and an electroresponsive indicatingdevice controlled by said contacts.

10. In combination with a car axle, a plate secured to one end of saidaxle and provided with a circular hole which is eccentric with respectto the axis of said axle, a fixed housing enclosing said plate, a firstshaft journaled in said housing, a frame pinned to said shaft in suchmanner that said frame is movable toward and away from the axle betweenav normal extreme position and another extreme position, meanscooperating with the free end of said frame for moving said framebetween its two extreme positions, a second shaft journaled in saidframe, a ring member pinned to said second shaft, a driving memberprovided with two curved arms which are pivotally attached to said ringmember at diametrically opposite points spaced 90 from said secondshaft, said driving member also being provided with a circular web whichis adapted to enter or be withdrawn from the hole in said plateaccording as said frame occupies its normal extreme position or itsother extreme position, the parts being so proportioned that when saidweb is within the hole in said plate and said axle is rotated saiddriving member and said shaft will be oscillated, an inertia memberpivotally mounted on said shaft, a rocker pinned to said shaft, meansincluding two contact fingers and a contact con" trolled by each fingerfor imparting to said inertia member in response to oscillation of saidrocker an accelerating force periodically changing in direction, acut-out switch operatively connected with said first shaft in suchinanner that said switch will be closed or open according as said frameis moved to its normal or its other extreme position, and anelectroresponsive indicating device connected in series with a source ofdirect current over said cut-out switch and said two contacts.

11. In combination with a car axle, a plate secured to one end of saidaxle and provided with a circular hole which is eccentric with respectto the axis of said axle, a fixed housing enclosing said plate, a firstshaft journaled in said housing, a frame pinned to said shaft in suchmanner that said frame is movable toward and away from the axis betweena normal extreme position and another extreme position, meanscooperating with the free end of said frame for moving said framebetween its two extreme positions, a second shaft journaled in saidframe, a ring member pinned to said second shaft, a driving memberprovided with two curved arms which are pivotally attached to said ringmember at diametrically opposite points spaced 90 from said secondshaft, said driving member also being provided with a circular web whichis adapted to enter or be withdrawn from the hole in said plateaccording as said frame occupies its normal extreme position or itsother extreme position, the parts being so proportioned that when saidweb is within the hole in said plate and said axle is rotated saiddriving member and said shaft will be oscillated, an inertia member inthe form of a hollow sphere mounted to oscillate on said second shaftWithin said ring member, a rocker pinned to said shaft within saidinertia member, means including two contact fingers and a contactcontrolled each finger for imparting to said inertia member in responseto oscillation of said rocker an accelerating force periodicallychanging in direction, an extension on said rocker cooperating with twoshoulders provided on said inertia member to limit the relative movementof said rocker and said inertia member, and speed indicating meanscontrolled by said contacts.

12. In combination with a car axle, a plate secured to one end of saidaxle and provided with a circular hole which is eccentric with respectto the axis of said axle, a fixed housing enclosing said plate, a firstshaft journaled in said housing, a frame pinned to said shaft in suchmanner that said frame is movable toward and away from the axle betweena normal extreme position and another extreme position, meanscooperating with the free end of said frame for moving said framebetween its two extreme positions, a second shaft journaled in saidframe, a ring member pinned to said second shaft, a driving memberprovided with two curved arms which are pivotally attached to saidring-member at diametrically opposite points spaced 90 from said secondshaft, said driving member also being provided with a circular web whichis adapted to enter or be withdrawn from the hole in said plateaccording as said frame occupies its normal extreme position or itsother extreme position, the parts being so proportioned that when saidweb is within the hole in said plate and said axle is rotated saiddriving member and said shaft will be oscillated, and inertia member inthe form of a hollow sphere mounted to oscillate on said second shaftwithin said ring member, a rocker pinned to said shaft within saidinertia member, fingers secured to said inertia member adjacent one endof said rocker, two resilient contact fingers secured to said rocker andeach provided with a contact member which cooperates with a differentone of said fixed contact members to form a contact, said contactfingers being so arranged that said contacts are biased to their closedpositions and that when said rocker is oscillated said fingers willalternately impart to said inertia member through the medium of saidcontacts oppositely acting accelerating forces, and an electroresponsiveindicating device controlled by said two contacts connected in series.

13. In combination with a car axle, a plate secured to one end of saidaxle and provided with a circular hole which is eccentric with respectto the axis of said axle, a fixed housing enclosing said plate, a firstshaft journaled in said housing, a frame pinned to said shaft in suchmanner that said frame is movable toward and away from the axle betweena normal extreme position and another extreme position, meanscooperating with the free end of said frame for moving said framebetween its two two fixed contact extreme positions, a second shaftjournaled in said frame, a ring member pinned to said second shaft, adriving member provided with two curved arms which are pivotallyattached to said ring member at diametrically opposite points space 90from said second shaft, said driving member also being provided with acircular web which is adapted to enter or be withdrawn from the holeinsaid plate according as said frame occupies its normal extreme positionor its other extreme position, the parts being so proportioned that whensaid web is within the hole in said plate and said axle is rotated saiddriving member and said shaft will be oscillated, an inertia member inthe form of a hollow sphere mounted to oscillate on said second shaftwithin said ring member, a rocker pinned to said shaft within saidinertia member, t'wo fixed contact fingers secured to said inertiamember adjacent one end of said 20 rocker, two resilient contact fingerssecured to said rocker and each provided with a contact member whichcooperates with a different one of said fixed contact members to form acontact, said contact fingers being so arranged that said contacts arebiased to their closed positions and that when said rocker is oscillatedsaid fingers will alternately impart to said inertia. member through themedium of said contacts oppositely acting accelerating forces, a relay,a reactance, a circuit for said relay including said two contacts andsaid reactance connected in series, and an asymmetric unit connected inmultiple with said relay and said reactance in said circuit.

14. Apparatus responsive to the speed of a movable body comprising arocker adapted to be oscillated at a frequency which varies with thespeed of the body, a pivoted inertia member, means including two contactfingers and a contact controlled by each finger for imparting to saidinertia member in response to oscillation of said rocker an acceleratingforce varying through repeated cycles during each of which the inertiamember is urged first in one direction by the one finger and then in theopposite direction by the other finger, and an electroresponsiveindicating device controlled by said contacts.

15. In combination with a rotatable member,

a frame movable between two extreme positions,

a rocker and a pivoted inertia member mounted in said frame, meanseffective when and only when said frame occupies one extreme positionfor operatively connecting said rocker with said rotatable member insuch manner that said rocker will be oscillated at a frequency whichvaries with the speed of said rotatable member, means including acontact finger and a contact controlled by said finger for imparting tosaid inertia member in response to oscillation of said rocker anaccelerating force periodically changing in direction, a cut-out switchoperated by said frame in such manner that said switch will be closed oropen according as said frame occupies its one or its other extremeposition, and

an electroresponsive indicating device controlled by said contact andsaid cut-out switch.

16. In combination with a rotatable member, a fixed casing, a firstshaft journaled in said casing, a frame secured to said first shaft andmovable with the shaft between two extreme positions, a second shaftjournaled in said frame, means effective when and only when said frameoccupies one extreme position for operatively connecting said secondshaft with said rotatable member in such manner that said second shaftwill be oscillated at a frequency which varies with the speed of saidrotatable member, an inertia member pivotally mounted on said secondshaft, a rocker pinned to said second shaft, means including two contactfingers and a contact controlled by each finger for imparting to saidinertia member in response to oscillation of said rocker an acceleratingforce periodically changing in direction, a cut-out switch operated bysaid first shaft in such manner that said switch will be closed or openaccording as said frame occupies its one or its other extreme position,and an electroresponsive indicating device controlled by said twocontacts and said cut-out switch.

17. Apparatus responsive to the speed of a movable body comprising afirst member which is periodically moved between two positions at afrequency which varies with the speed of the body, a movable inertiamember, means including two contacts for operatively connecting saidfirst member with said inertia member in such manner that during eachcyclic operation of said first member an accelerating force will betransmitted to said inertia member first in one direction through themedium of one contact and then in the opposite direction through themedium of the other contact, and an electroresponsive indicating devicecontrolled by said contacts.

18. Apparatus responsive to the speed of a movable body comprising afirst member which is periodically moved between two positions at afrequency which varies with the speed of the body, a movable inertiamember, means including two resilient members and a contact controlledby each member for operatively connecting said first member with saidinertia member in such manner that during each cyclic operation of saidfirst member an accelerating force will be transmitted to said inertiamember first in one direction through the medium of one resilient memberand then in the opposite direction through the medium of the otherresilient member, and an electroresponsive indicating'device controlledby said contacts.

19. Apparatus responsive to the speed of a movable body comprising afirst member which is periodically moved between two positions at afrequency which varies with the speed of the body, a movable inertiamember, means including two resilient members and a contact controlled Iby each member foroperatively connecting said first member with saidinertia member in such manner that during each cyclic operation of saidfirst member an accelerating force will be transmitted to said inertiamember first in one direction through the medium of one resilient memberand then in the opposite direction through the medium of the otherresilient member, the parts being so proportioned that for all speeds ofsaid body below a predetermined speed said contacts will remaincontinuously closed but that for all speeds above saidpredeterminedspeed said contacts will become alternately opened and closed, and anelectroresponsive indicating device controlled by said contacts.

20. Apparatus responsive to the speed of a movable body comprising afirst member which is periodically moved between two positions at afrequency which varies with the speed of the body, a movable inertiamember, means including two resilient members and a contact controlledby each member for operatively connecting said first member with saidinertia member in such manner that during each cyclic operation of saidfirst member an accelerating force will be transmitted to said inertiamember first in one direction through the medium of one resilient memberand then in the opposite direction through the medium of the otherresilient member, the parts being so proportioned that for all speeds ofsaid body below a predetermined speed said contacts will remaincontinuously closed but that for all speeds of said body above saidpredetermined speed said contacts will become alternately opened andclosed in such manner that the open time will increase as the speed ofthe body increases, and an electroresponsive device controlled by saidcontacts.

'21. Apparatus responsive to the speed of a movable body comprising afirst member which is periodically moved between two positions at afrequency which varies with the speed of the body, a movable inertiamember, means including two resilient members for operatively con=-necting said first member with said inertia member in such manner thatduring each cyclic operation of said first member an accelerating forcewill be transmitted to said inertia member first in one directionthrough the medium of one resilient member and then in the oppositedirection through the medium of the other resilient member, and twocontacts one controlled by each resilient member.

22. Apparatus responsive to the speed of a movable body comprising afirst member which is periodically moved between two positions at afrequency which varies with the speed of the body, a movable inertiamember, means including two resilient members for operatively connectingsaid first member with said inertia member in such manner that duringeach cyclic operationi of said first member an accelerating force willbe transmitted to said inertia member first in one direction through themedium of one. resilient member and then in the opposite directionthrough the medium of the other resilient member, and two contacts onecontrolled jointly by each resilient member and said inertia member.

23. Apparatus responsive to the speed of a movable body comprising afirst member which is periodically moved between two positions at afrequency which varies with the speed of the body, a movable inertiamember, means including two resilient members for operatively connectingsaid first member with said inertia member in such manner that duringeach cyclic operation of said first member an accelerating force will betransmitted to said inertia member first in one direction through themedium of one resilient member and then in the opposite directionthrough the medium of the other resilient member, and two contactscontrolled by said inertia membeer and said resilient members in suchmanner that said contacts will remain continuously closed as long as theaccelerating forces which are transmitted to said inertia member by saidresilient members are below predetermined values which depend upon thestiffness of said resilient members and the inertia of said inertiamember but that said contacts will become alternately opened and closedat a frequency which varies with the speed of the body when theaccelerating forces which are transmitted to said inertia member by saidresilient members exceed said predetermined values.

24. Apparatus responsive to the speed of a movable body comprising twomovable contact fingers, a contact controlled by each finger, means forbiasing said fingers to positions in which the contacts controlledthereby are closed, a floating lever, means attached to one point onsaid lever for imparting to said lever oscillating motion at a frequencywhich varies with the speed of said body, a movable fulcrum at a secondpoint on said lever normally held in a fixed position by the biasingforce which biases said contacts to their closed positions, a movableinertia member operatively connected with said lever at a third point insuch manner that oscillation of said lever tends to oscillate saidinertia member, and an electroresponsive indicating device controlled bysaid contacts. I

25. Apparatus responsive to the speed of a movable body comprising twomovable contact fingers, a contact controlled by each finger, means forbiasing said fingers to positions in which the contacts controlledthereby are closed, a floating lever, means attached to one point onsaid lever for imparting to said lever oscillating motion at a frequencywhich varies with the speed of said body, a movable fulcrum at a secondpoint .on said lever normally held in a fixed position by the biasingforce which biases said contacts to their closed positions, a movableinertia member operatively connected with said lever at a third point insuch manner that oscillation of said lever tends to oscillate saidinertia member, and an electroresponsive indicating device controlled bysaid contacts connected in series.

26. Apparatus responsive to the speed of a movable body comprising twomovable contact fingers, a contact controlled by each finger, means forbiasing said fingers to positions in which the contacts controlledthereby are closed, a floating lever, means attached to one point onsaid lever for imparting to said lever oscillating motion at a frequencywhich varies with the speed of said body, a movable fulcrum at a secondpoint on said lever normally held in a fixed position through the mediumof said contact fingers by the biasing force which biases said contactsto their closed positions, a movable inertia member operativelyconnected with said lever at a third point in such manner thatoscillation of said lever tends to oscillate said inertia member, and anelectroresponsive indicating device controlled by said contacts.

27. Apparatus responsive to the speed of a movable body comprising twomovable contact fingers, a contact controlled by each finger, means forbiasing said fingers to positions in which the contacts controlledthereby are closed, a crank which is periodically moved between twopositions at a frequency which varies with the speed of the body, arocker lever pivotally attached to said crank, a pivoted inertia member,means for operatively connecting said lever, said contact fingers andsaidinertia member in such manner that during each cyclic operation ofsaid crank an accelerating force will be transmitted to said inertiamember first in one direction through the medium of the one contactfinger and then in the other direction through the medium of the otherfinger in a manner which tends to move said fingers to positions inwhich the contacts controlled thereby are open, and an electroresponsiveindicating device controlled by said contacts.

28. Apparatus responsive to the speed of a movable body comprising twomovable contact fingers, a contact controlled by each finger, means forbiasing said fingers to positions in which the contacts controlledthereby are closed, a crank which is periodically moved between twopositions at a frequency which varies with the speed of the body, arocker lever pivotally attached to said crank, a pivoted inertia member,means for operatively connecting said lever, said contact fingers andsaid inertia member in such manner that during each cyclic operation ofsaid crank an accelerating force will be transmitted to said inertiamember first in one direction through the medium of the one contactfinger and then in the other direction through the medium of the otherfinger in a manner which tends to move said fingers to positions inwhich the contacts controlled thereby are open, and an electroresponsiveindicating device controlled by said contacts, the parts being soproportioned that said contacts will remain closed for all frequenciesof said crank below a predetermined frequency but will becomealternately opened for all frequencies of the crank above saidpredetermined speed.

29. Apparatus responsive to the speed of a movable body comprising twomovable contact fingers, a contact controlled by each finger, means forbiasing said fingers to a position in which the contact controlled byeach finger is closed, a crank which is periodically moved between twopositions at a frequency which varies with the speed of the body, apivoted inertia member, a rocker lever pivotally mounted at one end on acrank pin secured to said crank and provided at the opposite end with aslot which slidably receives a block mounted on a pin secured to saidinertia member, a contact operating bar pivotally attached to said leverintermediate the ends of the lever and provided at each end with aninsulating member which cooperates with a different one of said fingersfor at times operating the contacts, and an electroresponsive indicatingdevice controlled by said contacts.

30. Apparatus responsive to the speed of a movable body comprising acasing, a crank pivotally mounted in said casing, means connected withsaid crank for operatively connecting said crank with said body in suchmanner that said crank will be oscillated at a frequency which varieswith the speed of the body, a mandrel mounted in one end of the shaft ofsaid crank, an inertia member pivotally mounted on said mandrel, afloating rocker lever pivotally attached at one end to said crank andprovided at the other end with a slot which slidably receives a blockwhich is pivotally connected with said inertia member, a terminal boardsecured to said casing, two movable contact fingers secured to saidterminal board on the side opposite to said lever, a low resistancecontact member secured to the free end of each finger, two contactbrackets secured to said terminal board, two fixed contact membersmounted in each bracket and each cooperating with a different one ofsaid low resistance contact members to form a contact, a coil springstretched between said fingers and biasing said fingers to positions inwhich the contacts controlled thereby are closed, a contact operatingmember pivotally attached to said lever intermediate the ends of thelever by means of a pin which extends through a slot in said terminalboard, two insulating pieces one mounted in each I end of said contactoperating member and each cooperating at its free end with a guidesecured to a different one of said fingers, said fixed contact memberbeing so adusted that when both contacts are closed each insulatingpiece will engage the associated guide, and an electroresponsiveindicating device controlled by said contacts connected in series.

JOHN W. LIVINGSTON.

one adj ustably

